1. Field of the Invention
The present invention relates to wireless local area networks (LAN). More particularly, it relates to a method for mobile terminal access to a wireless LAN based on access point (AP) services and service parameters using the beacon frames of the AP.
2. Description of the Prior Art
Mobile terminals (MT) can associate with a wireless LAN based on the Service Set Identity (SSID) that is periodically broadcast by the APs in the beacon frames. Currently, SSID is a human readable byte string that is arbitrarily set by network administrators. In order for the MT to associate with a wireless LAN, the user, of the MT (i.e., the consumer) must manually set the SSID of a specific AP in the wireless LAN or configure the MT to choose any AP. In the latter case, generally the MT associates with the AP that has the highest signal strength.
There are several limitations of the current MT/wireless LAN association scheme. More particularly: 1) The network administrators must inform the users of the SSIDs of the available APs and the services they offer; 2) The users must manually configure their MTs to use either a specific SSID or any SSID; and 3) The SSIDs are arbitrarily set and provide no information about the services and/or capabilities of the AP.
In the case of public wireless LAN hot spots such as airports and hotels, the situation becomes more complex where several service providers deploy APs in the same geographical location. Thus, the visitors or guests who wish to use the wireless LAN services of a specific service provider must first determine the SSID of the AP that belongs to that service provider and then manually configure their MT. This can become unduly burdensome to the user, not to mention requires the user to have appropriate knowledge of how to configure their MT for such access.
Currently, there is no mechanism that allows the MTs to discover the services and service parameters offered by the APs and then automatically choose an AP based on user specified preferences. A partial solution that is currently available uses configuration profiles. Configuration profiles are simply a set of configuration options that are persistently stored on the MT. Thus, instead of manually configuring all the wireless LAN parameters every time the user changes a network association, he/she simply loads them from the configuration profile. This mechanism does not support any automatic selection of an AP based on the services that it offers, and still requires the users to have knowledge of the specific SSIDs.
It is therefore desirable for the MTs to learn the details of an AP without requiring any manual intervention by the user. Examples of some of these details could be: 1) Who is the provider of the wireless LAN service?; 2) What kind of services does it offer (Internet access, Walled-Garden services, etc.)?; and 3) What are the parameters of the offered services (Quality of Service, cost, etc.)?